This revised proposal requests the 5-year renewal of the Hebrew Rehabilitation Center for Aged (HRCA)/Harvard Research Nursing Home (RNH) Project. Over the past 20 years the RNH has become a unique, multidisciplinary collaboration of investigators from multiple academic institutions in Boston that share the common goal of conducting high-quality clinical research focused on prevalent, disabling, previously neglected syndromes that threaten the independence and quality of life of elderly people. Participating institutions are HRCA, Brigham and Women's Hospital, Beth Israel Deaconess Hospital, Boston University, and Harvard Medical School. The new project period will focus on the Mechanisms and Management of Falls in Old Age, exploring 3 important mechanisms underlying falls that have received very little attention by previous investigators. These include 1) cerebral hypoperfusion, 2) peripheral sensory deficits, and 3) musculoskeletal pain. Our previous work has resulted in new methodology to measure cerebral blood flow in elderly; to improve the detection of sensory stimuli and balance control through imperceptible mechanical noise applied to the feet; and to quantify pain and its functional implications. We will now examine these mechanisms prospectively in a diverse community-dwelling population of 800 people aged 70 or older. Our 3 research projects include: 1) Cerebrovascular Mechanisms of Falls in Old Age, PI: Lewis A. Lipsitz, MD; 2) Enhancing Balance in Elders with Falls or Sensory Deficits, PI: James J. Collins, PhD; and 3) Functional Consequences of Persistent Pain, PI: Suzanne Leveille, PhD. These will be supported by 3 cores: A) an Epidemiology Core, PI: Douglas P. Kiel, MD; B) a Data Management and Analysis Core, PI: Debbie M. Cheng, PhD; and C) a Research Administration and Development Core, PI: Lewis A. Lipsitz, MD. A Scientific Advisory Committee will review our progress annually and a Community Advisory Board will assist with recruitment and outreach. Our institutional commitments, longstanding collaboration among investigators, track record of productivity, administrative structure, and proven leadership all assure that this program will achieve its stated goals.